Multi-band color vision filters and method by LP-optimization

Abstract

The invention generally relates to optical filters that provide regulation and/or enhancement of chromatic and luminous aspects of the color appearance of light to human vision, generally to applications of such optical filters, to therapeutic applications of such optical filters, to industrial and safety applications of such optical filters when incorporated, for example, in radiation-protective eyewear, to methods of designing such optical filters, to methods of manufacturing such optical filters, and to designs and methods of incorporating such optical filters into apparatus including, for example, eyewear and illuminants.

What is claimed is: 
     
       1. A method for increasing red-green color discrimination for an observer with deuteranomalous or protanomalous color vision deficiency, the method comprising: providing the observer a multi-band optical filter through which to view colored objects, the optical filter having a spectral transmittance curve comprising:
 a plurality of pass-bands and stop-bands partitioning the visible spectrum, including, 
 three or more pass-bands interleaved with two or more stop-bands, wherein 
 each pass-band has a center, a width, a lower band boundary equal to the center minus half the width, an upper band boundary equal to the center plus half the width, and a mean transmittance, 
 each stop-band has a center, a width, a lower band boundary equal to the center minus half the width, an upper band boundary equal to the center plus half the width, and a mean transmittance, 
 the lower band boundary of each interleaved stop-band is the same as the upper band boundary of an adjacent pass-band, 
 the upper band boundary of each interleaved stop-band is the same as the lower band boundary of an adjacent pass-band, 
 each pass-band center is located between about 400 nanometers and about 700 nanometers and each pass-band width is between about 10 nanometers and about 110 nanometers, 
 each stop-band center is located between about 410 nanometers and about 690 nanometers and each stop-band width is between about 10 nanometers and about 80 nanometers, and 
 each of the interleaved stop-bands has a mean transmittance that is less than one half of the mean transmittance of an adjacent pass-band, and 
 a step feature on a side of one of the plurality of pass-bands, the step feature located between 580 nanometers and 610 nanometers, a spectral transmittance of the step feature is at least one fifth of a luminous transmittance of the optical filter, where the luminous transmittance is an average spectral transmittance of light through the optical filter weighted by the CIE 1924 photopic luminosity function, 
 the optical filter configured to increase red-green color discrimination for the observer with deuteranomalous or protanomalous color vision deficiency. 
 
     
     
       2. The method of  claim 1 , wherein the optical filter is configured to increase red-green color discrimination for observers with deuteranomalous color vision deficiency, the optical filter comprises
 a first pass-band having a center located between about 440 nanometers and about 455 nanometers and a width of between about 20 and about 40 nanometers, 
 a second pass-band having a center located between about 525 nanometers and about 545 nanometers and a width of between about 20 and about 50 nanometers, and 
 a third pass-band having a center located between about 610 nanometers and about 640 nanometers and a width of between about 30 and about 80 nanometers, 
 wherein each of the interleaved stop-bands has a width of at least about 40 nanometers and a mean transmittance that is less than about one fourth of the mean transmittance of an adjacent pass-band, and 
 a minimum spectral transmittance of the filter between about 475 nanometers and about 580 nanometers is at most about one fifth of the luminous transmittance of the filter. 
 
     
     
       3. The method of  claim 2 , wherein the first pass-band center is located at less than or equal to about 450 nanometers. 
     
     
       4. The method of  claim 2 , wherein the first pass-band center is located at less than or equal to about 445 nanometers. 
     
     
       5. The method of  claim 2 , wherein the third pass-band center is located at greater than or equal to about 625 nanometers. 
     
     
       6. The method of  claim 2 , wherein the third pass-band center is located at greater than or equal to about 635 nanometers. 
     
     
       7. The method of  claim 2 , wherein the second pass-band width is at most about 40 nanometers. 
     
     
       8. The method of  claim 2 , wherein the second pass-band width is at most about 35 nanometers. 
     
     
       9. The method of  claim 2 , wherein the second pass-band width is at most about 30 nanometers. 
     
     
       10. The method of  claim 2 , wherein the second pass-band center is located between about 535 nanometers and about 540 nanometers. 
     
     
       11. The method of  claim 2 , wherein the second pass-band center is located at about 535 nanometers. 
     
     
       12. The method of  claim 2 , wherein the minimum spectral transmittance of the filter between about 475 nanometers and about 580 nanometers is less than about one fifth of the luminous transmittance. 
     
     
       13. The method of  claim 2 , wherein the minimum spectral transmittance of the filter between about 475 nanometers and about 580 nanometers is less than about one tenth of the luminous transmittance. 
     
     
       14. The method of  claim 2 , wherein each of the interleaved stop-bands has a mean transmittance that is less than about one eighth of the mean transmittance of an adjacent pass-band. 
     
     
       15. The method of  claim 2 , wherein each of the interleaved stop-bands has a mean transmittance that is less than about one tenth of the mean transmittance of an adjacent pass-band. 
     
     
       16. The method of  claim 2 , wherein each of the interleaved stop-bands has a mean transmittance that is greater than about one sixteenth of the mean transmittance of an adjacent pass-band. 
     
     
       17. The method of  claim 2 , wherein
 the first pass-band has a center located at about 445 nanometers and a width of about 25 nanometers, 
 the second pass-band has a center located at about 530 nanometers and a width of about 45 nanometers, 
 the third pass-band has a center located at about 635 nanometers and a width of about 50 nanometers, 
 each of the interleaved stop-bands has a mean transmittance that is about one sixth of the mean transmittance of an adjacent pass-band. 
 
     
     
       18. The method of  claim 17 , wherein the optical filter is configured to increase red-green color discrimination for observers with mild deuteranomalous color vision deficiency. 
     
     
       19. The method of  claim 2 , wherein
 the first pass-band has a center located at about 445 nanometers and a width of about 25 nanometers, 
 the second pass-band has a center located at about 530 nanometers and a width of about 40 nanometers, 
 the third pass-band has a center located at about 640 nanometers and a width of about 50 nanometers, 
 each of the interleaved stop-bands has a mean transmittance that is about one eighth of the mean transmittance of an adjacent pass-band. 
 
     
     
       20. The method of  claim 19 , wherein the optical filter is configured to increase red-green color discrimination for observers with moderate deuteranomalous color vision deficiency. 
     
     
       21. The method of  claim 2 , wherein
 the first pass-band has a center located at about 440 nanometers and a width of about 25 nanometers, 
 the second pass-band has a center located at about 530 nanometers and a width of about 45 nanometers, 
 the third pass-band has a center located at about 640 nanometers and a width of about 50 nanometers, 
 each of the interleaved stop-bands has a mean transmittance that is about one eighth of the mean transmittance of an adjacent pass-band. 
 
     
     
       22. The method of  claim 21 , wherein the optical filter is configured to increase red-green color discrimination for observers with severe deuteranomalous color vision deficiency. 
     
     
       23. The method of  claim 2 , wherein the optical filter provides an (x,y) chromaticity coordinate that is at least about 0.05 units away from any point on the boundary of the average daylight color limit region defined according to industrial standard ANSI Z80.3-2010 section 4.6.3.1. 
     
     
       24. The method of  claim 2 , wherein the optical filter provides an (x,y) chromaticity coordinate of the yellow traffic signal that is within about 0.05 units of the point (0.313, 0.620), as defined by industrial standard ANSI Z80.3-2005 sections 5.6.3.1 and 4.6.3.1. 
     
     
       25. The method of  claim 1 , wherein the optical filter is configured to increase red-green color discrimination for observers with protanomalous color vision deficiency, the optical filter comprises
 a first pass-band having a center located between about 440 nanometers and about 455 nanometers and a width of between about 20 and about 40 nanometers, 
 a second pass-band having a center located between about 525 nanometers and about 545 nanometers and a width of between about 20 and about 45 nanometers, 
 a third pass-band having a center located between about 610 nanometers and about 640 nanometers and a width of between about 30 and about 80 nanometers, and 
 each of the interleaved stop-bands has a width of at least about 30 nanometers and a mean transmittance that is less than about one fourth of the mean transmittance of an adjacent pass-band, 
 a minimum spectral transmittance of the filter between about 475 nanometers and about 580 nanometers is at most about one fifth of the luminous transmittance of the filter. 
 
     
     
       26. The method of  claim 25 , wherein the first pass-band center is located at less than or equal to about 450 nanometers. 
     
     
       27. The method of  claim 25 , wherein the first pass-band center is located at less than or equal to about 445 nanometers. 
     
     
       28. The method of  claim 25 , wherein the first pass-band center is located at less than or equal to about 440 nanometers. 
     
     
       29. The method of  claim 25 , wherein the third pass-band center is located at greater than or equal to about 615 nanometers. 
     
     
       30. The method of  claim 25 , wherein the third pass-band center is located at greater than or equal to about 625 nanometers. 
     
     
       31. The method of  claim 25 , wherein the second pass-band width is at most about 40 nanometers. 
     
     
       32. The method of  claim 25 , wherein the second pass-band width is at most about 35 nanometers. 
     
     
       33. The method of  claim 25 , wherein the second pass-band width is at most about 30 nanometers. 
     
     
       34. The method of  claim 25 , wherein the second pass-band center is located between about 525 nanometers and about 535 nanometers. 
     
     
       35. The method of  claim 25 , wherein the second pass-band center is located about 530 nanometers. 
     
     
       36. The method of  claim 25 , wherein the minimum spectral transmittance of the filter between about 475 nanometers and about 580 nanometers is less than about one fifth of the luminous transmittance. 
     
     
       37. The method of  claim 25 , wherein the minimum spectral transmittance of the filter between about 475 nanometers and about 580 nanometers is less than about one tenth of the luminous transmittance. 
     
     
       38. The method of  claim 25 , wherein each of the interleaved stop-bands has a mean transmittance that is less than about one eighth of the mean transmittance of an adjacent pass-band. 
     
     
       39. The method of  claim 25 , wherein each of the interleaved stop-bands has a mean transmittance that is less than about one tenth of the mean transmittance of an adjacent pass-band. 
     
     
       40. The method of  claim 25 , wherein each of the interleaved stop-bands has a mean transmittance that is greater than about one sixteenth of the mean transmittance of an adjacent pass-band. 
     
     
       41. The method of  claim 25 , wherein
 the first pass-band has a center located at about 445 nanometers and a width of about 20 nanometers, 
 the second pass-band has a center located at about 525 nanometers and a width of about 40 nanometers, 
 the third pass-band has a center located at about 630 nanometers and a width of about 55 nanometers, 
 each of the interleaved stop-bands has a mean transmittance that is about one eighth of the mean transmittance of an adjacent pass-band. 
 
     
     
       42. The method of  claim 25 , wherein the optical filter provides an (x,y) chromaticity coordinate that is at least about 0.05 units away from any point on the boundary of the average daylight color limit region defined according to industrial standard ANSI Z80.3-2010 section 4.6.3.1. 
     
     
       43. The method of  claim 25 , wherein the optical filter provides an (x,y) chromaticity coordinate of the yellow traffic signal that is within about 0.05 units of the point (0.313, 0.620), as defined by industrial standard ANSI Z80.3-2005 sections 5.6.3.1 and 4.6.3.1.